Christner P J, Artlett C M, Conway R F, Jiménez S A
Division of Rheumatology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania 19107-5541, USA.
Arthritis Rheum. 2000 Nov;43(11):2598-605. doi: 10.1002/1529-0131(200011)43:11<2598::AID-ANR30>3.0.CO;2-8.
To develop a murine model for use in examining the role of microchimeric cells and certain chemical exposures in the pathogenesis of systemic sclerosis (SSc).
Female BALB/cJ retired breeder mice were bled before and after vinyl chloride injection. The DNA from their white blood cells was obtained, and the number of microchimeric cell equivalents was determined by quantitative polymerase chain reaction using DNA primers specific for the H-2Kb gene, a sequence not found in BALB/cJ mice. Skin was obtained at autopsy, embedded in paraffin, sectioned, and stained with Masson's trichrome. Hydroxyproline analyses were performed on 4-mm skin biopsy samples.
Microchimeric cells were identified and quantitated before and after 20 daily intraperitoneal injections of vinyl chloride. The number of microchimeric cells in the peripheral blood increased an average of 48-fold after treatment with vinyl chloride. Histologic examination of the skin of these same mice (which had an increased number of microchimeric cells) showed inflammation, with abundant fibroblasts and a heavy mononuclear infiltration in the dermis. The collagen fibers appeared densely packed and disorganized. Histologic examination of the skin of untreated retired breeder mice and treated virgin mice appeared normal. Quantitative assays to determine the collagen content of skin biopsy samples obtained from treated microchimeric mice compared with nontreated microchimeric or with treated nonmicrochimeric mice showed a 2-3-fold increase in collagen content in the treated microchimeric mice. Extraordinary splenomegaly was present in the vinyl chloride-treated microchimeric mice, accompanied by cellular infiltration and fibrosis.
The results suggest that vinyl chloride injections into BALB/cJ retired breeder mice lead to activation of microchimeric cells, which causes the cells to divide and multiply. The correlation between the 48-fold increase in microchimeric cells and the appearance of dermal inflammation and fibrosis similar to that of graft-versus-host disease suggests that activated microchimeric cells may be a necessary factor in the pathogenesis of autoimmune diseases such as SSc.
建立一种小鼠模型，用于研究微嵌合细胞和某些化学暴露在系统性硬化症（SSc）发病机制中的作用。
对雌性BALB/cJ退休繁殖小鼠在注射氯乙烯前后进行采血。获取其白细胞中的DNA，使用针对H-2Kb基因的DNA引物通过定量聚合酶链反应确定微嵌合细胞当量的数量，该序列在BALB/cJ小鼠中不存在。在尸检时获取皮肤，石蜡包埋，切片，并用Masson三色染色法染色。对4毫米皮肤活检样本进行羟脯氨酸分析。
在每天腹腔注射氯乙烯20次前后均鉴定并定量了微嵌合细胞。用氯乙烯处理后，外周血中的微嵌合细胞数量平均增加了48倍。对这些微嵌合细胞数量增加的相同小鼠的皮肤进行组织学检查，显示有炎症，真皮中有大量成纤维细胞和重度单核细胞浸润。胶原纤维显得密集堆积且排列紊乱。对未处理的退休繁殖小鼠和处理过的处女小鼠的皮肤进行组织学检查显示正常。与未处理的微嵌合小鼠或处理过的无微嵌合小鼠相比，对从处理过的微嵌合小鼠获得的皮肤活检样本进行胶原含量的定量测定，结果显示处理过的微嵌合小鼠的胶原含量增加了2至3倍。在氯乙烯处理的微嵌合小鼠中出现了异常的脾肿大，伴有细胞浸润和纤维化。
结果表明，向BALB/cJ退休繁殖小鼠注射氯乙烯会导致微嵌合细胞活化，从而使细胞分裂和增殖。微嵌合细胞增加48倍与类似于移植物抗宿主病的皮肤炎症和纤维化外观之间的相关性表明，活化的微嵌合细胞可能是自身免疫性疾病如SSc发病机制中的一个必要因素。
